Is this maybe a "sell high" scenario for twitter? Sounds like the article is suggesting that, while demand is still strong, the supply of available office space is rising.
Perhaps their thinking is to get the asset under lease while the price is still at it's current rate and then spend on expansion later if it's necessary (at theoretically lower prices based on the supply trend?).
Perhaps their thinking is to get the asset under lease while the price is still at it's current rate and then spend on expansion later if it's necessary (at theoretically lower prices based on the supply trend?).